WLANs aim to provide a network access service for wireless users, and to meet a demand of users for accessing network resources (for example, the Internet). Currently, many public places (for example, a shopping mall, a coffee shop, an airport, a conference center, and a library) are deployed with WLANs, and after accessing the WLANs, users can access a basic local service, or implement faster or cheaper Internet access. There is one type of application demand in the foregoing scenario, that is, a network service provider needs to quickly identify a user identity to provide a better service. For example, automatic network access is provided for a user who has visited the place before, or a larger network bandwidth is provided for a guest who frequently visits the place.
Currently, most wireless management software on a client device can set a WLAN access point (AP) configuration file and save an AP service set identifier (SSID) and corresponding access password to ensure direct access next time; however, the problem of such a method lies in that a user has to enter a password again and update the configuration file once the password is changed; as a result, fast network access cannot be implemented; and another problem lies in that an AP cannot verify a real identity of a mobile device, in other words, any mobile device having the access password can modify a media access control (MAC) address of the mobile device and be in disguise as another user (for example, a user with a high service level), so as to gain benefits.